This is the end of the preview.
Sign up
to
access the rest of the document.

Unformatted text preview: ly excitatory state, increase circuit to ﬁre
- has a lot to do when people are trying to think, motivate, processing info, learning • Glutamate: excitatory: cognitive, seizures, motivation
• GABA: inhibitory, seizures, anxiety; e.g., Anti-anxiety meds
(benzodiazepines (Valium, Xanax) help GABA bind more
- two different effects
effectively to post-synaptic receptors - PNS: paralytic agent
- CNS: higher cognitive process • Acetylcholine (ACh): PNS vs. CNS: muscle/motor vs.
higher cognition (learning, memory), plasticity, Alzheimer’s, etc.
- basic arousal function • Epinephrine/Nor-e: fundamental arousal/alertness fcts.
- depression
• Serotonin: mood, emotion, motivation, impulse control, etc.
• Dopamine: reward (+ motor functions., planning & many
higher-level interactions with cognitive functions.)
• and..... then there’s a huge variety of other peptides, implicated
in basically everything... :) -- reward and motor function = pleasure system
learning system Dopamine
- main function: deal with our pleasure Dopamine activity in the nucleus accumbens is
a practically universal PLEASURE
mechanism….and the common bond among
drugs of enjoyment, experimentation, and
abuse The Dopamine System
- overuse a neuron circuit = down regulates the response, decreasing the mechanism of the circuit Drugs of abuse
commandeer the brain’s natural reward
circuitry. Stimulation of this pathway
reinforces behavior, ensuring that what
you just did you will do again. Nestler & Malenka (2004): - therefore, learning is strongly affected by reward, and
the rewarding effects of, for e.g., cocaine are mediated
through the same mechanisms which have evolved for
highly functional, adaptive reasons, like learning and
motivation....kind of ironic, isn’t it? - Dopamine Junkies
- Depression, leaned helplessness, addictions (drugs) -> compulsive behaviors -> motivation
- VTA releases dopamine into N.A., amygdala, PFC, etc -> activation of motor &attentional systems The Split Brain
The two hemispheres of the brain are actually two
mini-brains connected by a bundle of fibers, the
corpus callosum - brain is a collection of brains
- from the late 1900s until the 1960s, debate raged
as to whether cutting the corpus callosum would
for several decades until the 1960s, it was not
help people with epilepsy -cut the corpus callouss to attempt to help peopleuncommon to
with epilepsy Being of two minds... Left hemisphere: logic, linear thinking, language
- language production Right hemisphere: emotion, spatial processing,
music
- spatial relationship "The great pleasure and feeling in my right brain is more
than my left brain can find the words to tell you."
Roger Sperry - left eye, right brain
- patient is asked to reach behind the screen and pick up the object
- two hemispheres are function independently Split-Brain Experiments
• When asked to
point to the item
that was seen, the
left hand (RH)
pointed to the
image seen by the
right hemispher...
View
Full Document